Effect of filament temperature on properties of hot wire CVD deposited nc-3C-SiC films from SiH4‐C2H2‐H2 mixture

摘要

n this study, nanocrystalline cubic SiC (nc-3C-SiC) thin films were deposited from SiH4 and C2H2 gas mixture by hot wire chemical vapour deposition technique. The influence of tungsten filament temperature T F on the film’s structural and optical properties was investigated. The deposited thin films were characterised by a variety of techniques, including Fourier transform infrared spectroscopy, Raman scattering, X-ray diffraction and ultraviolet‐visible‐near infrared spectroscopy. It was found that the film’s structure changed from microcrystalline Si into nc-3C-SiC with increasing T F from 1600 to 2000°C. An increase in T F enhanced the crystallinity of SiC films, and the optical band gap increased from 1·6 to 2·5 eV. Comparing with CH4, C2H2 could be easily decomposed at proper T F. Consequently, the carbon incorporation rate into the SiC film was intensively increased.